Abstract

Probabilistic reasoning biases have been widely associated with levels of delusional belief ideation (Galbraith, Manktelow & Morris, 2011; Lincoln, Ziegler, Mehl, & Rief, 2010; Speechley, Whitman, & Woodward, 2009; White & Mansell, 2009), however, little research has focused on biases occurring during every day reasoning (Galbraith, Manktelow & Morris, 2011), and moral and crime based reasoning (Wilkinson, Jones & Caulfield, 2011; Wilkinson, Caulfield & Jones, 2014). 235 participants were recruited across four experiments exploring crime based reasoning through different modalities and dual processing tasks. Study one explored delusional ideation when completing a visually presented crime based reasoning task. Study two explored the same task in an auditory presentation. Study three utilised a dual task paradigm to explore modality and executive functioning. Study four extended this paradigm to the auditory modality. The results indicated that modality and delusional ideation have a significant effect on individuals reasoning about violent and non-violent crime (p<0.05), which could have implication for the presentation of evidence in applied setting such as the courtroom.